Pichai will keep oversight of the Chrome Web browser and operating system while taking responsibility for Android, Chief Executive Officer Larry Page said in a blog today.

Under Rubin, Android surged ahead of Apple's software to command 70 percent of the operating systems on smartphones.

Pichai joined Google in 2004 and led the effort to roll out laptop computers that use the Chrome operating system.

Staying with Google, the company also today announced it bought a Canadian startup DNNresearch, which is specializing in getting machines to understand what people are trying to say.

DNNresearch was founded last year by University of Toronto professor Geoffrey Hinton, who is renowned for machine learning work with "profound implications" for areas such as speech recognition, computer vision and language understanding.

"Together with two of my recent graduate students, I am betting on Google's team to be the epicenter of future breakthroughs," Hinton said in a post at Google+ social network.

"That means we'll soon be joining Google to work with some of the smartest engineering minds to tackle some of the biggest challenges in computer science."

Google did not specify where it intends to focus the DNNresearch team but the company has a clear interest in tuning its search engine to a world in which people speak queries into smartphones or use snapped pictures as search terms.